High-resolution radio frequency spectral analysis with photon echo chirp transform in an Er:YSO crystal

We demonstrate implementation of the chirp transform algorithm with photon echoes in an Er³⁺:YSO crystal at 1536 nm for application to spectral analysis of RF signals. The principle and features of the technique are presented using a simple picture in the time-frequency plane. Experimental results with low-bandwidth RF signals demonstrate 40-kHz spectral resolution and a time-bandwidth product of 500. Extension to broad-band RF signals is discussed.